<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>权重练习</title>
    <style>
        .nav{
            color: red;
        }
        /*  继承的权重是0*/
        li{
            color: blueviolet;
        }

        /* 把第一个li颜色改为 绿色加粗 */
        /* .zy的权重是10   */
        .zy{
            color: green;
            font-weight:   700;
        }
    </style>
</head>
<body>
    <ul class="nav">
        <li class="zy">人生四大悲</li>
        <li>家里没宽带</li>
        <li>网速不够快</li>
        <li>手机没流量</li>
        <li>学校没wifi</li>
    </ul>
</body>
</html>